A switchover valve of the type used to connect the output of a mixing valve either to an overhead shower or to a tub faucet is described in German patent document 2,841,998 issued 27 Sept. 1978 to Andreas Ruth et al. Here the valve elements are a circular ceramic valve plate fixed in the valve housing and formed with a pressurized inlet port and a plurality of outlet ports, with the inlet port centered on the axis and the outlet ports spaced angularly about the axis. A circular ceramic control plate lies flat atop this disk and has a central hole in permanent alignment with the inlet port and an outfeed hole connected to it that can be aligned by rotation of the control plate with any of the outlet ports. Thus when the outfeed hole is aligned with one of the outlet ports it connects it to the pressurized inlet port, and in at least one position of the valve the outfeed hole is between outlet ports and blocked so that there is no fluid flow through the valve.
The main disadvantage of this type of valve is that it is fairly bulky. The diameters of the control and valve plates must be large enough to accommodate the various ports so that the resultant structure is too large to be accommodated to today's architectural styles demanding slim shapes in plumbing fittings.